constraints(): predicate only gets intersection

src/constraints.hh

@@ -31,11 +31,8 @@ namespace PPS {
       {
         if(intersection.boundary())
         {
-          // center of face
-          auto testpoint = referenceElement(intersection.geometry()).position(0,0);
-
           // skip if this isn't a Dirichlet boundary
-          if (!isDirichlet(intersection,testpoint))
+          if (!isDirichlet(intersection))
             continue;
 
           const int face = intersection.indexInInside();

src/driver.hh

@@ -53,10 +53,12 @@ void driver (const GV& gv, Dune::ParameterTree& ptree)
   using LFE = Dune::Q1LocalFiniteElement<DF, RF, dim>;
   //== Exercise 2 {
 #ifndef NITSCHE
-  auto blambda = [&](const auto& i, const auto& x)
-    {return problem.b(i,x);};
+  auto isDirichlet = [&](const auto& intersection) {
+    auto testpoint = referenceElement(intersection.geometry()).position(0,0);
+    return problem.b(intersection,testpoint);
+  };
   std::set<std::size_t> cc;
-  PPS::constraints(blambda,gv,LFE{}, cc); // assemble constraints
+  PPS::constraints(isDirichlet,gv,LFE{}, cc); // assemble constraints
   std::cout << "constrained dofs=" << cc.size() << " of "
             << gv.indexSet().size(gv.dimension) << std::endl;
 #endif